This study examines the adult antisocial outcomes and developmental histories of psychopathic children. Three separable, but related, outcomes are assessed-- psychopathy (in Cleckley's sense), antisocial personality disorder, and offending. Participants are the 508 members of the middle sample of the Pittsburgh Youth Study, which consists of 254 high-risk and 254 not-at-risk inner-city boys who were enrolled in the longitudinal study when they were 10 years old. When the boys were 12.5, they were assessed with a measure of psychopathy among other measures. This study proposes to re-assess the participants at age 21 in order to examine the developmental course and outcomes of early psychopathy. By extending the longitudinal study and including a specific focus on psychopathy, we plan to resolve several issues in the research on psychopathy at both the child and adult level. Specifically, we plan to learn these things: 1) whether psychopathy is stable across an eight-year period from late childhood to early adulthood; 2) whether the concept of "fledgling psychopathy" aids in predicting, over previous conduct problems, family factors, and other forms of psychopathology who becomes antisocial in adulthood and who does not; 3) if there are individual strengths that protect a child at-risk for adult psychopathy from developing it in adulthood; 4) if there are ameliorative and rehabilitative social experiences or environmental characteristics that protect children at risk. 5) what factors account for and mediate the stability in psychopathy across time; 6) if subclinical or so-called "successful" psychopaths can be identified and what factors distinguish them from unsuccessful psychopaths.